GB2281323A - A sealing strip for,e.g. guttering - Google Patents

Abstract

A sealing strip 1 intended to be received within a sealing channel 2 to seal against an adjacent length of guttering. The sealing strip comprises an upper portion 3 to engage the under-surface of the guttering and a lower portion 7. The upper portion and the lower portion are inter-connected by four legs 8, 9, each of which is thinner than the upper portion. The legs collapse in a predetermined manner when the sealing strip is compressed, the legs moving to a position in which they form a substantially solid bridge between the upper portion and the lower portion of the sealing strip to resist lateral movement. <IMAGE>

Description

DESCRIPTION OF INVENTION "IMPROVEMENTS IN OR RELATING TO A SEAL" THE PRESENT INVENTION relates to a seal and more particularly relates to a seal intended for use in a guttering system.

In a guttering system it is conventional to provide a seal in the form of a sealing strip received in a channel which is formed in a seat, which seat is intended to receive the end of a length of guttering. The length of guttering is clipped in position within the seat so that the under-surface of the length of guttering engages the top surface of the seal and compresses the seal, with the result that the seal is biassed, by its own resistance, against the outer surface of the guttering in a water-tight manner.

There have been many prior proposed seals of this general type. The desired characteristics for a seal are that the seal may be readily extruded, and that the seal provides a good sealing effect. Also it is desirable that the seal should be able to withstand transverse movement of the length of guttering retained within the seat (that is to say movement of the guttering transversely to the axis of the seal) without any adverse effect on the seal. The guttering may move transversely of the seal due to thermal expansion and contraction of the guttering and may also move in this manner when the guttering is being assembled.

Many prior art seals, under such transverse movement of the guttering, tend to "roll" or bunch, or even may become dislodged from the channel in which the sealing strip is received. This is undesirable and the present invention seeks to provide an improved seal.

According to this invention there is provided a sealing strip adapted to be received within a sealing channel, the sealing strip comprising an upper portion adapted to engage the under-surface of an overlying element, and having a lower support portion, the upper portion and the lower support portion being inter-connected by a plurality of legs which are thinner than the upper portion, the legs being adapted to collapse in a predetermined manner when the sealing strip is compressed, the legs moving to a position in which they form a substantially solid bridge between the upper portion and the lower portion of the sealing strip to resist lateral movement.

Preferably the legs comprise at least two legs which are located one substantially at each side of the strip, each of said legs being cranked and being adapted to deform when downward pressure is applied on the upper support region, the legs, when deformed, providing a substantially rigid connection between the upper support region and the lower support region.

Conveniently the upper portion is a substantially planar portion.

While the top of the upper portion may comprise a substantially planar surface preferably the upper portion is formed with a plurality of elongate protrusions each adapted to engage the under-surface of the overlying element.

Advantageously the protrusions on the upper surface of the upper portion comprise a plurality of substantially triangular cross-section protrusions.

Conveniently the sealing strip comprises additional trapezoidal projections provided at the edges of the upper portion.

Advantageously the lower support portion is provided with inverted substantially "V"-shaped recesses formed in the under-surface thereof.

Conveniently the lower support portion is provided with laterally projecting wings adapted to grip the side walls of a channel in which the sealing strip is adapted to be received.

Preferably the said two legs have the cranked portions directed inwardly of the sealing strip, an aperture being formed in the sealing strip adjacent the cranked portion of each leg to enable each leg to be deformed, bending at the cranked part, when downward pressure is applied on the upper support region.

Advantageously the legs comprise two further legs each extending inwardly from a position adjacent the outer edge of the lower support portion towards the centre of the upper portion.

Conveniently an aperture is defined adjacent the said two further legs, beneath the central region of the upper portion.

Preferably the thickness of the said two further legs is less than the thickness of the said upper portion.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described, by way of example, with reference to the accompanying drawings in which FIGURE 1 is a cross-sectional view of a sealing strip in accordance with the invention, the strip being illustrated just above a channel dimensioned to receive the sealing strip, and FIGURE 2 is a cross-sectional view of the sealing strip of Figure 1 when located within the channel with a length of guttering located in position in engagement with the seal.

Referring to the drawings, a sealing strip in accordance with the invention comprises an extrusion 1 which is adapted to be received within a channel 2.

The sealing strip 1 is moulded of a suitable plastic rubber or other resilient material. The sealing strip 1 presents an upper substantially planar portion 3 which carries, on its upper surface a plurality of evenly spaced substantially triangular cross-sectioned upstanding ribs 4. Each rib may have a rounded or flat top or apex.

In the present embodiment four such ribs are provided located substantially centrally. Adjacent each side of the planar portion is an upstanding trapezoidal projection 5, each trapezoidal projection presenting a substantially flat upper-surface 6 which is co-aligned with the apices of the triangle cross-sectioned ribs 4. Thus each projection 5 is of the same height as the ribs 4.

The upper substantially planar portion 3 of the sealing strip 1 is supported above a lower support portion 7 by means of four support legs. There are two outer support legs 8 each of the same form and two inner support legs 9, also of the same form, so that the entire arrangement of the legs is symmetrical about a notional, vertical, central line.

Each outer leg 8 is in the form of a cranked leg having an upper limb 10 which extends from the lower surface of the upper substantially planar portion 2 directly below a trapezoidal projection 5, the upper limb extending inwardly at a convenient angle towards the centre of the sealing strip 1. The upper limb 10 is connected to a lower limb 11, which is angled outwardly from the centre of the sealing strip 1, by means of an arcuate bend or "knee" 12. The knee 12 is directed inwardly towards the centre of the sealing strip 1. The lower limb 11 extends to part of the lower support portion 7 in the region of the edge of the sealing strip 1. A generally "arrow-head" configuration aperture 13 is defined adjacent the knee 12.

Two sides of the aperture 13 are defined by the upper limb 10 and the lower limb 11 of the leg 8, and an upper edge of the aperture 13 is defined by the under-surface of the substantially planar portion 3. The lower inclined edge of each arrow-head shaped aperture 13 is defined by the upper part of the leg 9.

Each leg 9 extends inwardly towards the centre of the sealing strip 1 from a position adjacent the outer-most part of the lower support portion 7. Thus the legs 9 are inwardly inclined from almost the outer-most edge of the sealing strip, and terminate below the substantially planar portion 3 in a central thickened region of the planar portion 3.

A diamond-shaped aperture 14 is formed in the centre of the strip, the upper-most edges of the diamondshaped aperture being defined by the lower edges of the legs 9, and the lower edges of the diamond-shaped aperture extending downwardly into the lower support portion 7. The lower support portion 7 has a central projection 15 substantially aligned with the diamond-shaped aperture, which projection is flanked by two inverted "V"-shaped recesses 16 formed in the lower surface of the support portion. The edges of each recess 16 are parallel respectively with a lower edge of the diamond-shaped aperture 9 and the lower edge of the arrow-head-shaped aperture 13. The lower surface of the projection 15 is planar.

The lower support portion 7 terminates, at each edge of the sealing strip 1, with a triangular sectioned outwardly directed wing 17, the total width across the wings 17 being slightly greater than the total width across the channel 2 that is to receive the sealing strip 1. The lower part of each wing defines, with the adjacent inverted "V"-shape recess, a downwardly directed point.

The upper surface of each wing 17 is a substantially horizontal surface and the lower limb 11 of the leg 8 extends upwardly from this horizontal surface.

It is to be noted that the thickness of each leg 8 is less than the thickness of the upper substantially planar portion 3 of the sealing strip 1. Also, the thickness of each leg 9 is less than the thickness of the horizontal support portion 7.

When the sealing strip 1 is inserted in the channel 2, the wings 17, which have an overall width greater than the width of the channel, are deflected upwardly, and serve resiliently to retain the strip in position within the channel 2. This is of benefit when assembling a guttering element which incorporates a sealing strip as described, since, typically, the sealing strip is inserted into the guttering element whilst the guttering element is inverted. The wings 17 resiliently grip the sides of the channel 2, thus minimising the risk that the sealing strip will inadvertently fall out of the channel 2.

When the sealing strip is initially located in the channel 2 the triangular projections 4 and the trapezoidal projections 5 extend above the top of the channel 2.

When a guttering component 18 is placed in position adjacent the channel 2 (and here reference may be made to Figure 2) the guttering component 18 will engage the projections 4 and 5 and will tend to compress the sealing strip by pressing downwardly on the sealing strip. As the sealing strip is compressed the outer legs 8 will each bend at the knee 12. The knee will thus be driven substantially horizontally into the aperture 13. The upper surface of the upper limb 10 will eventually come into contact with the upper side of the arrow-shaped aperture 13 and the lower surface of the lower limb 11 will come into contact with the lower edge of the arrow-shaped aperture 13.The lower surface of the upper limb 10 will come into contact with the upper surface of the lower limb 11, as can be seen most clearly in Figure 2, and thus there is a substantially firm connection between the trapezoidal connection 5 and the underlying support structure 7.

The legs each form a substantially solid bridge between the upper substantially planar portion and the lower support portion, so there is a substantially rigid inter-connection between these portions.

Each leg 9 will kink about its central point, that is to say the point located between the arrow-head aperture 13 and the diamond-shaped aperture 14, the uppermost part of the legs 9, which effectively form the thickened region of the upper substantially planar portion 3, dropping into the diamond-shaped aperture 14.

The lower support portion 7 may also be slightly compressed, with the inverted "V"-shaped recesses 16 being slightly flattened, and the points between the recesses 16 and the wings 17 also being slightly flattened. Thus, parts of the lower support portion are compressed providing a resilient upward bias, through the legs 8 and 9, which themselves add to the upward bias, to the upper substantially planar portion 3.

It is thus to be appreciated that the sealing strip 1 will be deformed in a resilient manner, and the inherent resilience of the sealing strip will tend to bias the upper substantially planar portion 3 upwardly so that the projections 4 and 5 make firm sealing contact with the under-surface of an overlying guttering element 18.

However, if the guttering element 18 tends to move transversely of the sealing strip 1 (i.e. to the left or to the right as shown in Figure 2), whilst the trapezoidal projections 5 may tend to move inwardly towards the centre of the channel 2, this movement is resisted by the engagement of the two limbs of the leg 8 and the opposed edges of the arrow-head-shaped aperture 13. Similarly, the configuration of the legs 9, when collapsed (as shown in Figure 2) tends to resist lateral movement of the top part of the strip relative to the bottom part of the strip.

Even if the legs 8 are not fully bent, so that there is space, for example, between the top of the limb 12 and the top edge of the arrow-head aperture 13, the leg may move slightly, permitting the trapezoidal projections 5 to move also, but then the leg will make contact with the adjacent parts of the sealing strip, again locking the projection against transverse movement.

Consequently, the strip as described possesses very good characteristics, providing a good degree of sealing, and resisting any tendency "roll" or be drawn out of the channel 2 as a consequence of lateral movement of an overlying guttering element.

Whilst the invention has been described with reference to one embodiment it is to be appreciated that modifications may be effected without departing from the scope of the invention.

Claims (14)

CLAIMS:

1. A sealing strip adapted to be received within a sealing channel, the sealing strip comprising an upper portion adapted to engage the under-surface of an overlying element, and having a lower support portion, the upper portion and the lower support portion being inter-connected by a plurality of legs which are thinner than the upper portion, the legs being adapted to collapse in a predetermined manner when the sealing strip is compressed, the legs moving to a position in which they form a substantially solid bridge between the upper portion and the lower portion of the sealing strip to resist lateral movement.

2. A sealing strip according to Claim 1 wherein the legs comprise at least two legs which are located one substantially at each side of the strip, each of said legs being cranked and being adapted to deform when downward pressure is applied on the upper support region, the legs, when deformed, providing a substantially rigid connection between the upper support region and the lower support region.

3. A sealing strip according to Claim 1 or Claim 2 wherein the upper portion is a substantially planar portion.

4. A sealing strip according to any one of the preceding Claims wherein the upper portion is formed with a plurality of elongate protrusions each adapted to engage the under-surface of the overlying element.

5. A sealing strip according to Claim 4 wherein the protrusions on the upper surface of the upper portion comprise a plurality of substantially triangular crosssection protrusions.

6. A sealing strip according to Claim 5 wherein the sealing strip comprises additional trapezoidal projections provided at the edges of the upper portion.

7. A sealing strip according to any one of the preceding Claims wherein the lower support portion is provided with inverted substantially "V"-shaped recesses formed in the under-surface thereof.

8. A sealing strip according to any one of the preceding Claims wherein the lower support portion is provided with laterally projecting wings adapted to grip the side walls of a channel in which the sealing strip is adapted to be received.

9. A sealing strip according to Claim 2 or any Claim dependent thereon wherein the said two legs have the cranked portions directed inwardly of the sealing strip, an aperture being formed in the sealing strip adjacent the cranked portion of each leg to enable each leg to be deformed, bending at the cranked part, when downward pressure is applied on the upper support region.

10. A sealing strip according to Claim 2 or any Claim dependent thereon wherein the legs comprise two further legs each extending inwardly from a position adjacent the outer edge of the lower support portion towards the centre of the upper portion.

11. A sealing strip according to Claim 10 wherein an aperture is defined adjacent the said two further legs, beneath the central region of the upper portion.

12. A sealing strip wherein the thickness of the said two further legs is less than the thickness of the said upper portion.

13. A sealing strip substantially as herein described with reference to and as shown in the accompanying drawings.

14. Any novel feature or combination of features disclosed herein.